<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        ul li {
            list-style: none;
            width: 200px;
            height: 100px;
            /* border: 1px solid #000; */
            /* 控制容器文本水平居中（非块级元素居中） */
            text-align: center;
        }

        .item1 {
            background-color: #489151;
        }

        .item2 {
            background-color: #117379;
        }

        .item3 {
            background-color: #cb5608;
        }

        .item4 {
            background-color: purple;
        }

        .item5 {
            background-color: aqua;
        }

        ul {
            margin: 0;
            padding: 0;
            display: flex;
            width: 100%;
            height: 700px;
            /* justify-content: space-around; */
            /* justify-content: space-between; */
            /* align-items: center;
            flex-direction: column; */
            /* background-color: #787170b3; */
            /* flex-wrap: wrap; */
            flex-flow: row wrap;
            align-content: center;
            /* align-content: flex-start; */
        }

        li {
            /* flex-grow: 0;
            /* 父容器空间不够，子容器不缩小 */
            /* flex-shrink: 0;
            flex-basis: 100px; */
            /* flex: 1 0; */
        }

        .item2 {
            /* order: -1; */
        }
    </style>
</head>

<body>
    <ul>
        <li class="item1">1</li>
        <li class="item2">2</li>
        <li class="item3">3</li>
        <li class="item4">4</li>
        <li class="item5">5</li>

    </ul>
</body>

</html>